[deliverable/binutils-gdb.git] / bfd / cpu-m68k.c

/* BFD library support routines for architectures.
   Copyright (C) 1990-2020 Free Software Foundation, Inc.
   Hacked by Steve Chamberlain of Cygnus Support.

   This file is part of BFD, the Binary File Descriptor library.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
   MA 02110-1301, USA.  */

#include "sysdep.h"
#include "bfd.h"
#include "libbfd.h"
#include "opcode/m68k.h"
#include "cpu-m68k.h"

static const bfd_arch_info_type *
bfd_m68k_compatible (const bfd_arch_info_type *a,
		     const bfd_arch_info_type *b);

#define N(name, print,d,next)  \
{  32, 32, 8, bfd_arch_m68k, name, "m68k",print,2,d,bfd_m68k_compatible, \
   bfd_default_scan, bfd_arch_default_fill, next, 0 }

static const bfd_arch_info_type arch_info_struct[] =
  {
    N(bfd_mach_m68000,  "m68k:68000", FALSE, &arch_info_struct[1]),
    N(bfd_mach_m68008,  "m68k:68008", FALSE, &arch_info_struct[2]),
    N(bfd_mach_m68010,  "m68k:68010", FALSE, &arch_info_struct[3]),
    N(bfd_mach_m68020,  "m68k:68020", FALSE, &arch_info_struct[4]),
    N(bfd_mach_m68030,  "m68k:68030", FALSE, &arch_info_struct[5]),
    N(bfd_mach_m68040,  "m68k:68040", FALSE, &arch_info_struct[6]),
    N(bfd_mach_m68060,  "m68k:68060", FALSE, &arch_info_struct[7]),
    N(bfd_mach_cpu32,   "m68k:cpu32", FALSE, &arch_info_struct[8]),
    N(bfd_mach_fido,    "m68k:fido",  FALSE, &arch_info_struct[9]),

    /* Various combinations of CF architecture features */
    N(bfd_mach_mcf_isa_a_nodiv, "m68k:isa-a:nodiv",
      FALSE, &arch_info_struct[10]),
    N(bfd_mach_mcf_isa_a, "m68k:isa-a",
      FALSE, &arch_info_struct[11]),
    N(bfd_mach_mcf_isa_a_mac, "m68k:isa-a:mac",
      FALSE, &arch_info_struct[12]),
    N(bfd_mach_mcf_isa_a_emac, "m68k:isa-a:emac",
      FALSE, &arch_info_struct[13]),
    N(bfd_mach_mcf_isa_aplus, "m68k:isa-aplus",
      FALSE, &arch_info_struct[14]),
    N(bfd_mach_mcf_isa_aplus_mac, "m68k:isa-aplus:mac",
      FALSE, &arch_info_struct[15]),
    N(bfd_mach_mcf_isa_aplus_emac, "m68k:isa-aplus:emac",
      FALSE, &arch_info_struct[16]),
    N(bfd_mach_mcf_isa_b_nousp, "m68k:isa-b:nousp",
      FALSE, &arch_info_struct[17]),
    N(bfd_mach_mcf_isa_b_nousp_mac, "m68k:isa-b:nousp:mac",
      FALSE, &arch_info_struct[18]),
    N(bfd_mach_mcf_isa_b_nousp_emac, "m68k:isa-b:nousp:emac",
      FALSE, &arch_info_struct[19]),
    N(bfd_mach_mcf_isa_b, "m68k:isa-b",
      FALSE, &arch_info_struct[20]),
    N(bfd_mach_mcf_isa_b_mac, "m68k:isa-b:mac",
      FALSE, &arch_info_struct[21]),
    N(bfd_mach_mcf_isa_b_emac, "m68k:isa-b:emac",
      FALSE, &arch_info_struct[22]),
    N(bfd_mach_mcf_isa_b_float, "m68k:isa-b:float",
      FALSE, &arch_info_struct[23]),
    N(bfd_mach_mcf_isa_b_float_mac, "m68k:isa-b:float:mac",
      FALSE, &arch_info_struct[24]),
    N(bfd_mach_mcf_isa_b_float_emac, "m68k:isa-b:float:emac",
      FALSE, &arch_info_struct[25]),
    N(bfd_mach_mcf_isa_c, "m68k:isa-c",
      FALSE, &arch_info_struct[26]),
    N(bfd_mach_mcf_isa_c_mac, "m68k:isa-c:mac",
      FALSE, &arch_info_struct[27]),
    N(bfd_mach_mcf_isa_c_emac, "m68k:isa-c:emac",
      FALSE, &arch_info_struct[28]),
    N(bfd_mach_mcf_isa_c_nodiv, "m68k:isa-c:nodiv",
      FALSE, &arch_info_struct[29]),
    N(bfd_mach_mcf_isa_c_nodiv_mac, "m68k:isa-c:nodiv:mac",
      FALSE, &arch_info_struct[30]),
    N(bfd_mach_mcf_isa_c_nodiv_emac, "m68k:isa-c:nodiv:emac",
      FALSE, &arch_info_struct[31]),

    /* Legacy names for CF architectures */
    N(bfd_mach_mcf_isa_a_nodiv, "m68k:5200", FALSE, &arch_info_struct[32]),
    N(bfd_mach_mcf_isa_a_mac,"m68k:5206e", FALSE, &arch_info_struct[33]),
    N(bfd_mach_mcf_isa_a_mac, "m68k:5307", FALSE, &arch_info_struct[34]),
    N(bfd_mach_mcf_isa_b_nousp_mac, "m68k:5407", FALSE, &arch_info_struct[35]),
    N(bfd_mach_mcf_isa_aplus_emac, "m68k:528x", FALSE, &arch_info_struct[36]),
    N(bfd_mach_mcf_isa_aplus_emac, "m68k:521x", FALSE, &arch_info_struct[37]),
    N(bfd_mach_mcf_isa_a_emac, "m68k:5249", FALSE, &arch_info_struct[38]),
    N(bfd_mach_mcf_isa_b_float_emac, "m68k:547x",
      FALSE, &arch_info_struct[39]),
    N(bfd_mach_mcf_isa_b_float_emac, "m68k:548x",
      FALSE, &arch_info_struct[40]),
    N(bfd_mach_mcf_isa_b_float_emac, "m68k:cfv4e", FALSE, 0),
  };

const bfd_arch_info_type bfd_m68k_arch =
  N(0, "m68k", TRUE, &arch_info_struct[0]);

/* Table indexed by bfd_mach_arch number indicating which
   architectural features are supported.  */
static const unsigned m68k_arch_features[] =
{
  0,
  m68000|m68881|m68851,
  m68000|m68881|m68851,
  m68010|m68881|m68851,
  m68020|m68881|m68851,
  m68030|m68881|m68851,
  m68040|m68881|m68851,
  m68060|m68881|m68851,
  cpu32|m68881,
  fido_a|m68881,
  mcfisa_a,
  mcfisa_a|mcfhwdiv,
  mcfisa_a|mcfhwdiv|mcfmac,
  mcfisa_a|mcfhwdiv|mcfemac,
  mcfisa_a|mcfisa_aa|mcfhwdiv|mcfusp,
  mcfisa_a|mcfisa_aa|mcfhwdiv|mcfusp|mcfmac,
  mcfisa_a|mcfisa_aa|mcfhwdiv|mcfusp|mcfemac,
  mcfisa_a|mcfhwdiv|mcfisa_b,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfmac,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfemac,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|mcfmac,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|mcfemac,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|cfloat,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|cfloat|mcfmac,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|cfloat|mcfemac,
  mcfisa_a|mcfhwdiv|mcfisa_c|mcfusp,
  mcfisa_a|mcfhwdiv|mcfisa_c|mcfusp|mcfmac,
  mcfisa_a|mcfhwdiv|mcfisa_c|mcfusp|mcfemac,
  mcfisa_a|mcfisa_c|mcfusp,
  mcfisa_a|mcfisa_c|mcfusp|mcfmac,
  mcfisa_a|mcfisa_c|mcfusp|mcfemac,
};

/* Return the count of bits set in MASK  */
static unsigned
bit_count (unsigned mask)
{
  unsigned ix;

  for (ix = 0; mask; ix++)
    /* Clear the LSB set */
    mask ^= mask & -mask;
  return ix;
}

/* Return the architectural features supported by MACH */

unsigned
bfd_m68k_mach_to_features (int mach)
{
  if ((unsigned)mach
      >= sizeof (m68k_arch_features) / sizeof (m68k_arch_features[0]))
    mach = 0;
  return m68k_arch_features[mach];
}

/* Return the bfd machine that most closely represents the
   architectural features.  We find the machine with the smallest
   number of additional features.  If there is no such machine, we
   find the one with the smallest number of missing features.  */

int bfd_m68k_features_to_mach (unsigned features)
{
  int superset = 0, subset = 0;
  unsigned extra = 99, missing = 99;
  unsigned ix;

  for (ix = 0;
       ix != sizeof (m68k_arch_features) / sizeof (m68k_arch_features[0]);
       ix++)
    {
      unsigned this_extra, this_missing;

      if (m68k_arch_features[ix] == features)
	return ix;
      this_extra = bit_count (m68k_arch_features[ix] & ~features);
      if (this_extra < extra)
	{
	  extra = this_extra;
	  superset = ix;
	}

      this_missing = bit_count (features & ~m68k_arch_features[ix]);
      if (this_missing < missing)
	{
	  missing = this_missing;
	  superset = ix;
	}
    }
  return superset ? superset : subset;
}

static const bfd_arch_info_type *
bfd_m68k_compatible (const bfd_arch_info_type *a,
		     const bfd_arch_info_type *b)
{
  if (a->arch != b->arch)
    return NULL;

  if (a->bits_per_word != b->bits_per_word)
    return NULL;

  if (!a->mach)
    return b;
  if (!b->mach)
    return a;

  if (a->mach <= bfd_mach_m68060 && b->mach <= bfd_mach_m68060)
    /* Merge m68k machine. */
    return a->mach > b->mach ? a : b;
  else if (a->mach >= bfd_mach_cpu32 && b->mach >= bfd_mach_cpu32)
    {
      /* Merge the machine features.  */
      unsigned features = (bfd_m68k_mach_to_features (a->mach)
			   | bfd_m68k_mach_to_features (b->mach));

      /* CPU32 and Coldfire are incompatible.  */
      if ((~features & (cpu32 | mcfisa_a)) == 0)
	return NULL;

      /* Fido and Coldfire are incompatible.  */
      if ((~features & (fido_a | mcfisa_a)) == 0)
	return NULL;

      /* ISA A+ and ISA B are incompatible.  */
      if ((~features & (mcfisa_aa | mcfisa_b)) == 0)
	return NULL;

      /* ISA B and ISA C are incompatible.  */
      if ((~features & (mcfisa_b | mcfisa_c)) == 0)
	return NULL;

      /* MAC and EMAC code cannot be merged.  */
      if ((~features & (mcfmac | mcfemac)) == 0)
	return NULL;

      /* CPU32 is compatible with Fido except that Fido does not
	 support tbl instructions.  Warn when the user wants to mix
	 the two.  */
      if ((a->mach == bfd_mach_cpu32 && b->mach == bfd_mach_fido)
	  || (a->mach == bfd_mach_fido && b->mach == bfd_mach_cpu32))
	{
	  static int cpu32_fido_mix_warning;
	  if (!cpu32_fido_mix_warning)
	    {
	      cpu32_fido_mix_warning = 1;
	      _bfd_error_handler ("warning: linking CPU32 objects with fido objects");
	    }
	  return bfd_lookup_arch (a->arch,
				  bfd_m68k_features_to_mach (fido_a | m68881));
	}

      return bfd_lookup_arch (a->arch, bfd_m68k_features_to_mach (features));
    }
  else
    /* They are incompatible.  */
    return NULL;
}
Commit	Line	Data
252b5132	1	/* BFD library support routines for architectures.
b3adc24a	2	Copyright (C) 1990-2020 Free Software Foundation, Inc.
252b5132 RH	3	Hacked by Steve Chamberlain of Cygnus Support.
252b5132 RH	4
3e602632	5	This file is part of BFD, the Binary File Descriptor library.
252b5132	6
3e602632 NC	7	This program is free software; you can redistribute it and/or modify
3e602632 NC	8	it under the terms of the GNU General Public License as published by
cd123cb7	9	the Free Software Foundation; either version 3 of the License, or
3e602632	10	(at your option) any later version.
252b5132	11
3e602632 NC	12	This program is distributed in the hope that it will be useful,
	13	but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	GNU General Public License for more details.
252b5132	16
3e602632 NC	17	You should have received a copy of the GNU General Public License
3e602632 NC	18	along with this program; if not, write to the Free Software
cd123cb7 NC	19	Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
cd123cb7 NC	20	MA 02110-1301, USA. */
252b5132	21
252b5132	22	#include "sysdep.h"
3db64b00	23	#include "bfd.h"
252b5132	24	#include "libbfd.h"
266abb8f	25	#include "opcode/m68k.h"
f5c5b7c1	26	#include "cpu-m68k.h"
252b5132	27
0b2e31dc NS	28	static const bfd_arch_info_type *
	29	bfd_m68k_compatible (const bfd_arch_info_type *a,
	30	const bfd_arch_info_type *b);
	31
252b5132	32	#define N(name, print,d,next) \
b7761f11	33	{ 32, 32, 8, bfd_arch_m68k, name, "m68k",print,2,d,bfd_m68k_compatible, \
aebcfb76	34	bfd_default_scan, bfd_arch_default_fill, next, 0 }
252b5132 RH	35
252b5132 RH	36	static const bfd_arch_info_type arch_info_struct[] =
3cac17ae	37	{
3e602632 NC	38	N(bfd_mach_m68000, "m68k:68000", FALSE, &arch_info_struct[1]),
	39	N(bfd_mach_m68008, "m68k:68008", FALSE, &arch_info_struct[2]),
	40	N(bfd_mach_m68010, "m68k:68010", FALSE, &arch_info_struct[3]),
	41	N(bfd_mach_m68020, "m68k:68020", FALSE, &arch_info_struct[4]),
	42	N(bfd_mach_m68030, "m68k:68030", FALSE, &arch_info_struct[5]),
	43	N(bfd_mach_m68040, "m68k:68040", FALSE, &arch_info_struct[6]),
266abb8f NS	44	N(bfd_mach_m68060, "m68k:68060", FALSE, &arch_info_struct[7]),
266abb8f NS	45	N(bfd_mach_cpu32, "m68k:cpu32", FALSE, &arch_info_struct[8]),
3bdcfdf4	46	N(bfd_mach_fido, "m68k:fido", FALSE, &arch_info_struct[9]),
266abb8f NS	47
266abb8f NS	48	/* Various combinations of CF architecture features */
0b2e31dc	49	N(bfd_mach_mcf_isa_a_nodiv, "m68k:isa-a:nodiv",
266abb8f	50	FALSE, &arch_info_struct[10]),
9840d27e	51	N(bfd_mach_mcf_isa_a, "m68k:isa-a",
266abb8f	52	FALSE, &arch_info_struct[11]),
9840d27e	53	N(bfd_mach_mcf_isa_a_mac, "m68k:isa-a:mac",
266abb8f	54	FALSE, &arch_info_struct[12]),
9840d27e	55	N(bfd_mach_mcf_isa_a_emac, "m68k:isa-a:emac",
266abb8f	56	FALSE, &arch_info_struct[13]),
9840d27e	57	N(bfd_mach_mcf_isa_aplus, "m68k:isa-aplus",
266abb8f	58	FALSE, &arch_info_struct[14]),
9840d27e	59	N(bfd_mach_mcf_isa_aplus_mac, "m68k:isa-aplus:mac",
266abb8f	60	FALSE, &arch_info_struct[15]),
9840d27e	61	N(bfd_mach_mcf_isa_aplus_emac, "m68k:isa-aplus:emac",
266abb8f	62	FALSE, &arch_info_struct[16]),
9840d27e	63	N(bfd_mach_mcf_isa_b_nousp, "m68k:isa-b:nousp",
266abb8f	64	FALSE, &arch_info_struct[17]),
9840d27e	65	N(bfd_mach_mcf_isa_b_nousp_mac, "m68k:isa-b:nousp:mac",
266abb8f	66	FALSE, &arch_info_struct[18]),
9840d27e	67	N(bfd_mach_mcf_isa_b_nousp_emac, "m68k:isa-b:nousp:emac",
266abb8f	68	FALSE, &arch_info_struct[19]),
9840d27e	69	N(bfd_mach_mcf_isa_b, "m68k:isa-b",
266abb8f	70	FALSE, &arch_info_struct[20]),
9840d27e	71	N(bfd_mach_mcf_isa_b_mac, "m68k:isa-b:mac",
266abb8f	72	FALSE, &arch_info_struct[21]),
9840d27e	73	N(bfd_mach_mcf_isa_b_emac, "m68k:isa-b:emac",
266abb8f	74	FALSE, &arch_info_struct[22]),
9840d27e	75	N(bfd_mach_mcf_isa_b_float, "m68k:isa-b:float",
266abb8f	76	FALSE, &arch_info_struct[23]),
9840d27e	77	N(bfd_mach_mcf_isa_b_float_mac, "m68k:isa-b:float:mac",
266abb8f	78	FALSE, &arch_info_struct[24]),
9840d27e KH	79	N(bfd_mach_mcf_isa_b_float_emac, "m68k:isa-b:float:emac",
9840d27e KH	80	FALSE, &arch_info_struct[25]),
9a2e615a NS	81	N(bfd_mach_mcf_isa_c, "m68k:isa-c",
	82	FALSE, &arch_info_struct[26]),
	83	N(bfd_mach_mcf_isa_c_mac, "m68k:isa-c:mac",
	84	FALSE, &arch_info_struct[27]),
	85	N(bfd_mach_mcf_isa_c_emac, "m68k:isa-c:emac",
	86	FALSE, &arch_info_struct[28]),
8d100c32 KH	87	N(bfd_mach_mcf_isa_c_nodiv, "m68k:isa-c:nodiv",
	88	FALSE, &arch_info_struct[29]),
	89	N(bfd_mach_mcf_isa_c_nodiv_mac, "m68k:isa-c:nodiv:mac",
	90	FALSE, &arch_info_struct[30]),
	91	N(bfd_mach_mcf_isa_c_nodiv_emac, "m68k:isa-c:nodiv:emac",
	92	FALSE, &arch_info_struct[31]),
266abb8f NS	93
266abb8f NS	94	/* Legacy names for CF architectures */
8d100c32 KH	95	N(bfd_mach_mcf_isa_a_nodiv, "m68k:5200", FALSE, &arch_info_struct[32]),
	96	N(bfd_mach_mcf_isa_a_mac,"m68k:5206e", FALSE, &arch_info_struct[33]),
	97	N(bfd_mach_mcf_isa_a_mac, "m68k:5307", FALSE, &arch_info_struct[34]),
	98	N(bfd_mach_mcf_isa_b_nousp_mac, "m68k:5407", FALSE, &arch_info_struct[35]),
	99	N(bfd_mach_mcf_isa_aplus_emac, "m68k:528x", FALSE, &arch_info_struct[36]),
	100	N(bfd_mach_mcf_isa_aplus_emac, "m68k:521x", FALSE, &arch_info_struct[37]),
	101	N(bfd_mach_mcf_isa_a_emac, "m68k:5249", FALSE, &arch_info_struct[38]),
0b2e31dc	102	N(bfd_mach_mcf_isa_b_float_emac, "m68k:547x",
8d100c32	103	FALSE, &arch_info_struct[39]),
9840d27e	104	N(bfd_mach_mcf_isa_b_float_emac, "m68k:548x",
8d100c32	105	FALSE, &arch_info_struct[40]),
0b2e31dc	106	N(bfd_mach_mcf_isa_b_float_emac, "m68k:cfv4e", FALSE, 0),
3cac17ae	107	};
252b5132 RH	108
252b5132 RH	109	const bfd_arch_info_type bfd_m68k_arch =
b34976b6	110	N(0, "m68k", TRUE, &arch_info_struct[0]);
266abb8f NS	111
	112	/* Table indexed by bfd_mach_arch number indicating which
	113	architectural features are supported. */
68ffbac6	114	static const unsigned m68k_arch_features[] =
266abb8f NS	115	{
	116	0,
	117	m68000\|m68881\|m68851,
	118	m68000\|m68881\|m68851,
	119	m68010\|m68881\|m68851,
	120	m68020\|m68881\|m68851,
	121	m68030\|m68881\|m68851,
	122	m68040\|m68881\|m68851,
	123	m68060\|m68881\|m68851,
	124	cpu32\|m68881,
3bdcfdf4	125	fido_a\|m68881,
266abb8f NS	126	mcfisa_a,
	127	mcfisa_a\|mcfhwdiv,
	128	mcfisa_a\|mcfhwdiv\|mcfmac,
	129	mcfisa_a\|mcfhwdiv\|mcfemac,
266abb8f NS	130	mcfisa_a\|mcfisa_aa\|mcfhwdiv\|mcfusp,
	131	mcfisa_a\|mcfisa_aa\|mcfhwdiv\|mcfusp\|mcfmac,
	132	mcfisa_a\|mcfisa_aa\|mcfhwdiv\|mcfusp\|mcfemac,
	133	mcfisa_a\|mcfhwdiv\|mcfisa_b,
	134	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfmac,
	135	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfemac,
0b2e31dc NS	136	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp,
	137	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|mcfmac,
	138	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|mcfemac,
266abb8f NS	139	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|cfloat,
	140	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|cfloat\|mcfmac,
	141	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|cfloat\|mcfemac,
9a2e615a NS	142	mcfisa_a\|mcfhwdiv\|mcfisa_c\|mcfusp,
	143	mcfisa_a\|mcfhwdiv\|mcfisa_c\|mcfusp\|mcfmac,
	144	mcfisa_a\|mcfhwdiv\|mcfisa_c\|mcfusp\|mcfemac,
8d100c32 KH	145	mcfisa_a\|mcfisa_c\|mcfusp,
	146	mcfisa_a\|mcfisa_c\|mcfusp\|mcfmac,
	147	mcfisa_a\|mcfisa_c\|mcfusp\|mcfemac,
266abb8f NS	148	};
	149
	150	/* Return the count of bits set in MASK */
	151	static unsigned
	152	bit_count (unsigned mask)
	153	{
	154	unsigned ix;
	155
	156	for (ix = 0; mask; ix++)
	157	/* Clear the LSB set */
	158	mask ^= mask & -mask;
	159	return ix;
	160	}
	161
	162	/* Return the architectural features supported by MACH */
	163
	164	unsigned
	165	bfd_m68k_mach_to_features (int mach)
	166	{
	167	if ((unsigned)mach
	168	>= sizeof (m68k_arch_features) / sizeof (m68k_arch_features[0]))
	169	mach = 0;
	170	return m68k_arch_features[mach];
	171	}
	172
	173	/* Return the bfd machine that most closely represents the
	174	architectural features. We find the machine with the smallest
	175	number of additional features. If there is no such machine, we
	176	find the one with the smallest number of missing features. */
	177
	178	int bfd_m68k_features_to_mach (unsigned features)
	179	{
	180	int superset = 0, subset = 0;
	181	unsigned extra = 99, missing = 99;
	182	unsigned ix;
	183
	184	for (ix = 0;
	185	ix != sizeof (m68k_arch_features) / sizeof (m68k_arch_features[0]);
	186	ix++)
	187	{
	188	unsigned this_extra, this_missing;
68ffbac6	189
266abb8f NS	190	if (m68k_arch_features[ix] == features)
	191	return ix;
	192	this_extra = bit_count (m68k_arch_features[ix] & ~features);
	193	if (this_extra < extra)
	194	{
	195	extra = this_extra;
	196	superset = ix;
	197	}
68ffbac6	198
266abb8f NS	199	this_missing = bit_count (features & ~m68k_arch_features[ix]);
	200	if (this_missing < missing)
	201	{
	202	missing = this_missing;
	203	superset = ix;
	204	}
	205	}
	206	return superset ? superset : subset;
	207	}
0b2e31dc NS	208
	209	static const bfd_arch_info_type *
	210	bfd_m68k_compatible (const bfd_arch_info_type *a,
	211	const bfd_arch_info_type *b)
	212	{
	213	if (a->arch != b->arch)
	214	return NULL;
	215
	216	if (a->bits_per_word != b->bits_per_word)
	217	return NULL;
	218
	219	if (!a->mach)
	220	return b;
	221	if (!b->mach)
	222	return a;
68ffbac6	223
0b2e31dc NS	224	if (a->mach <= bfd_mach_m68060 && b->mach <= bfd_mach_m68060)
	225	/* Merge m68k machine. */
	226	return a->mach > b->mach ? a : b;
9840d27e	227	else if (a->mach >= bfd_mach_cpu32 && b->mach >= bfd_mach_cpu32)
0b2e31dc	228	{
9840d27e	229	/* Merge the machine features. */
0b2e31dc NS	230	unsigned features = (bfd_m68k_mach_to_features (a->mach)
0b2e31dc NS	231	\| bfd_m68k_mach_to_features (b->mach));
0b2e31dc	232
9840d27e KH	233	/* CPU32 and Coldfire are incompatible. */
	234	if ((~features & (cpu32 \| mcfisa_a)) == 0)
	235	return NULL;
	236
3bdcfdf4 KH	237	/* Fido and Coldfire are incompatible. */
	238	if ((~features & (fido_a \| mcfisa_a)) == 0)
	239	return NULL;
	240
a9d34880 RS	241	/* ISA A+ and ISA B are incompatible. */
	242	if ((~features & (mcfisa_aa \| mcfisa_b)) == 0)
	243	return NULL;
	244
9a2e615a NS	245	/* ISA B and ISA C are incompatible. */
	246	if ((~features & (mcfisa_b \| mcfisa_c)) == 0)
	247	return NULL;
	248
a9d34880 RS	249	/* MAC and EMAC code cannot be merged. */
	250	if ((~features & (mcfmac \| mcfemac)) == 0)
	251	return NULL;
	252
3bdcfdf4 KH	253	/* CPU32 is compatible with Fido except that Fido does not
	254	support tbl instructions. Warn when the user wants to mix
	255	the two. */
	256	if ((a->mach == bfd_mach_cpu32 && b->mach == bfd_mach_fido)
	257	\|\| (a->mach == bfd_mach_fido && b->mach == bfd_mach_cpu32))
	258	{
	259	static int cpu32_fido_mix_warning;
	260	if (!cpu32_fido_mix_warning)
	261	{
	262	cpu32_fido_mix_warning = 1;
4eca0228	263	_bfd_error_handler ("warning: linking CPU32 objects with fido objects");
3bdcfdf4 KH	264	}
	265	return bfd_lookup_arch (a->arch,
	266	bfd_m68k_features_to_mach (fido_a \| m68881));
	267	}
	268
a9d34880	269	return bfd_lookup_arch (a->arch, bfd_m68k_features_to_mach (features));
0b2e31dc NS	270	}
	271	else
	272	/* They are incompatible. */
	273	return NULL;
	274	}